How Much Do I Weigh?
In Kids Space Place at Space Center Houston, you will be
able to step on scales and find out how much you weigh
on three other planets. Get a jump start here and find out
how much you weigh an all 9 planets, the Moon, and in
In space without gravity pulling down on them, Astronauts
are essentially weightless. It is important to explore the
difference between mass and weight. While Astronauts
may not weigh anything in space and can float around
freely, their body shape and size does not change. They
up just as
much space as they do here on Earth.
This is the important difference
between mass and weight. We will
explore this difference a little further
and then your students can practice
seeing how much they would weigh on
Weight measures the attraction of two
objects to each other. When you step
on a scale, it is actually measuring the
attraction between you and the Earth
and gives you a number in pounds or
kilograms. Our mass is the amount of matter that we consist of. This mass does not
change when we change planets. However, if we went from Earth to Mars, our weight
would change because Mars has less gravity than
Earth. Gravity is a force pulling matter together.
Earth’s gravity wants to keep everything pulled
toward the center of the planet keeping us from
falling off the Earth. Every object in space has
gravity. Stars, moons, and planets all have
gravity. The amount of gravity the have depends
on their size. So, a small planet has less and larger
planet has more gravity. Just like the planets, a
person with more mass has more gravity and
therefore weighs more.
When Astronauts visited the Moon, which has onesixth of our gravity, they bounced around on the
surface as if they were floating with each step.
See the pictures comparing the size of the planets
on the following page. Then on page 3 follow the activity procedure for your students to
find their weight on other planets and planetary objects.
How Much Do I Weigh?
1. Weigh yourself or guess your weight here on
2. Record your mass in the chart below. Your
mass will be your weight here on Earth.
3. Use the chart below and the following formula
to calculate your weight on other planetary
objects. Weight = mass x gravity